New owner / autocrosser

[jasyatz]

Yes. if you've got TOE IN at the rear, you've adjusted the bar in the wrong direction. You can get to zero easy and to 1/8" out with about a turn and a half. 1/4" out if you really crank it tight at 2 turns.

Camber is adjustable, just need to have your alignment guy put it where you want it.

 

[Bentiac]

That's what I thought! And the number of turns helps a lot.

Camber is maxed out at -2.0… according to the same guy who got -2.7 degrees with camber bolts and stock ride height.

 

[Bentiac]

Adjusted the rear toe... with the tape measure it seems to be between 1/16 and 1/8 toe out now...

Our last event of the year is this Sunday. Still on my ZIIs and the temperatures are getting close to zero and surprisingly dry... will be interesting to see how they do compared to continentals.

 

[Bentiac]

Just an update, I finally have -3.00 camber using two camber bolts on each side and no slotting... I could have gone up to -3.5 if I wanted to. I'm a little worried about slippage and the k-sport upper holes but I'll find out on Sunday after the first 2014 autox.

BTW with R1Rs being banned in 2015, what are people planning to switch to? ZII or the Rival???

 

[Andres3165]

Enjoy 2014 with the r1r's , great for your weather, new tires will be out next year. Rivals is a good option (very fast at the beginning), but they don't last as adverticed. RE11-A's are a good option. Just got a set of rivals for Fla. weather but getting Toyo's for National competitions.

Andres

 

[jasyatz]

BTW with R1Rs being banned in 2015, what are people planning to switch to? ZII or the Rival???

I'm sticking with the Rivals, down in size to 205. I tried the ZII last year in the 205 and just about took the edges off the front tires in one event with around -2.5 camber up front so I'm guessing more camber was needed or to try them on a 7" wide rim and not the 7.5".

I was happy with the Rivals last year in the 225, I hear the 205 are a big quicker on the 7.5" rim, so I'll see what happens.

My car was a tenth or so off Joe Austin (who finished 4th at Nats last year) with very few performance mods, stock or there about weight, and no tune. This was right after Nationals at our last fall event in 2013. I'm hopeful this year now that I've spent some time (and money) getting some more power and "added lightness", the car will be much stronger. Joe drove my car with the ZII and said it needed if felt a little numb and needed more tire. He suggested going back to the Rivals, and that was my plan anyway, but I'd be up,for trading my soul to try the R1R.

Slippage with camber bolts is a possibility, I've seen it on just about every track/solo car I've worked on. You just can't get enough torque on them to make the stick. A hardened 14mm bolt would be a better option as you can torque then to ridiculous high values without stripping or breakage. That's on my to do list as soon as all this winter is behind us.

My region is hosting the Tour in May at MetLife, our first event isnt for another 6 weeks, so I'm anxious to get out there an see how good the car is. For now i have to live vicariously through others who are fortunate enough to have decent weather in January and a site that's NOT hosting the Super Bowl this year!

Good luck tomorrow, and have fun.

Jeff

 

[Bentiac]

I'm getting R1Rs for the next event and based on our club rule I can run it until April 2015 (our winter series follows the previous year rules). I'm quiet happy with the front setup of the car and R1Rs are probably the biggest bang for the buck right now. My rear suspension is sitting a bit too high and could be lowered another half an inch or so but I'll worry about that next year... the rake is actually helping somewhat with braking.

At -3 (compared to -2.5) the car is much more forgiving when entering corners fast and getting on power early but it definitely didn't like my first few runs where I wasn't as aggressive and tires were cold. At 2 degrees C on ZII, it was a handful even with a half lift at the wrong place. Finished 9th / 87 drivers... need another .5 sec from the car + much better driving to be competitive in the bulk part.

 

[Bentiac]

Updates on the car: We have been fine tuning the car but now on R1R/6UL and the results have been fantastic... the car has paxed first last two events locally.

One thing that's been bothering us however is that the rear tires skip rather than slide and this is normally a sign of too much rebound. I however think this could be caused by too little damping rate and not necessarily too much rebound. The rear is 400 spring rate on k-sport dampers... any thoughts?

 

[jasyatz]

That's exactly what we had until we installed the Tri Point bar...It's a camber/toe thing where when the rear gets loaded, it wants to toe in to reduce the oversteer. When we added the bar, stopped hopping around.. Went back to a softer spring rate, but you are right in where we found a sweet spot 350/400. With the stiffer valved B-spec shocks in the rear, the skip/hop was much worse. The rear seems to want a higher bump shock with less rebound. The K sports just aren't compressed enough (neither are any of the other OTS shocks available) but if you want to add the Tri point bar, it WILL fix the skipping, but you'll need a straight pipe exhaust...see my build thread for pics on what it does to the muffler.

Andres I think is running the AST rears that Andy Hollis had custom built for the car. Both of these guys have had success with the Ksports fronts and the AST rears. Neither had the Tri Point bar, they both ran the RB rear stiffener.

That's an awesome result, Nice to see the car get Top Pax.

 

[zps2004]

What tires are you running and at what pressure? Are you sure it is the suspension and not the tires which are hopping?

 

[Bentiac]

The K sports just aren't compressed enough (neither are any of the other OTS shocks available) but if you want to add the Tri point bar, it WILL fix the skipping, but you'll need a straight pipe exhaust...see my build thread for pics on what it does to the muffler.

I have the Tripoint bar installed, should have mentioned earlier. I have it setup for neutral to a bit of toe in for the winter and I didn't have any issues with my exhaust being in the way:

What tires are you running and at what pressure? Are you sure it is the suspension and not the tires which are hopping?

R1Rs at 29PSI in rain and standing water, also tried 31-32 (all cold measurements).

My co-driver thinks that we need an extra 50lb in the rear springs rate... he thinks we are rolling too much and lifting / bouncing the inside tire... I'm thinking more damping is needed, not sure! The ASTs are kind of pricy... I wonder if re-valving the k-sports would be an option and worth it?

I should also add that my rear is sitting about 3/4 of an inch higher than the front (and that probably explains the exhaust not hitting). If I go with higher spring rate, I'll probably get a shorter spring to fix this.

 

[zps2004]

From looking at your spring rates those shouldn't be the issue. I know if you have too much of a imbalance between the front and the rear it can cause hopping, but yours isn't bad.

Now the shocks I would say could be suspect because I personally really don't like k-sports, and also if you have the fronts on full stiff still that would probably cause some hopping being too stiff for the tires.

Also your pressure seems a little low to me. You might be getting to the point where your tires have a softer spring rate than your suspension which can cause some funkyness too.

 

[Bentiac]

Also your pressure seems a little low to me. You might be getting to the point where your tires have a softer spring rate than your suspension which can cause some funkyness too.

I think I recall Andy running with 25 PSI R&F... but I could be wrong.

Anyone here has custom valved k-sports?

 

[zps2004]

That could be, but with the AST's in the rear it could probably control it. I say just give it a try one time with the rears closer to 40. Easy enough to do without spending money.

 

[Bentiac]

I'll give that a try!

Meanwhile I emailed K-sport to see if they do any custom-valving and here was the response:

"The shock we sell is the only one we have for that little car. WE do not make any other valved strut for it at this time."

I guess AST is the way to go!

 

[Bentiac]

Was just going through my storage this weekend and I came across a pair of control arms from a car that I owned 10+ years ago… they looked roughly the same size and shape as the torsion bar that corksport sells. Being bored I took it to the car and tried it on the torsion beam and…. what are the chances… it fits perfectly. Got a couple of bolts and installed it… drove around and no negative feedback yet but I'll have to wait until the next event (in two weeks). The only downside (or upside) is that they have poly bushing fitted at each end. The bar itself is 25mm in diameter.

They are GM control arms part #10409660 2x 1/2-4 1/2 studs and bolts… here is what the bar looks like:

 

[jasyatz]

Good find! Press out those poly bushings and get some delrin inserts made and you've got your solid torsion bar.

 

[Bentiac]

Quick updates:
-Took off the bar above... didn't feel any difference to justify the added weight (this is with the tripoint bar still in place)
-2.4lb battery installed
-Going with higher spring rates in the rear for the summer (350=>400)
-Driver side fixed back seats will go in once I receive my floor mount
-Thinking of getting a super trapp and deleting the second cat

 

[jasyatz]

Was just going through my storage this weekend and I came across a pair of control arms from a car that I owned 10+ years ago… they looked roughly the same size and shape as the torsion bar that corksport sells. Being bored I took it to the car and tried it on the torsion beam and…. what are the chances… it fits perfectly. Got a couple of bolts and installed it… drove around and no negative feedback yet but I'll have to wait until the next event (in two weeks). The only downside (or upside) is that they have poly bushing fitted at each end. The bar itself is 25mm in diameter.

They are GM control arms part #10409660 2x 1/2-4 1/2 studs and bolts… here is what the bar looks like:

I added this and makes a huge difference with the softer Bilstein springs. The rear used to creak and pop a lot from the TriPoint bar, after installing the GM bar, it's quiet now. I too am adding a bit of rear spring in the car, thinking in the 350-400lb range. I used the Dorman equivalent 905-501. It's $18 shipped on Amazon.. it's 3/4" square stock instead of 25mm round. It's about 5lb..so well worth the slight weight gain.

Supertraps are raspy and a pain to deal with, but make great power. Extreme has the Burns unit and it's loud, but has a nice tone to it. Above 3000 rpm you can't notice the difference from my RB muffler.

 

[Bentiac]

I'm sure if you don't have any other torsion bar this would be an effective way to strengthen the rear bar and cheap too but I think with the tri-point it was redundant for me. It might come in handy again if I decide to remove the tripoint to go lower a bit (at the moment I don't have enough clearance due to the tripoint bar).

Supertraps are raspy and a pain to deal with, but make great power. Extreme has the Burns unit and it's loud, but has a nice tone to it. Above 3000 rpm you can't notice the difference from my RB muffler.

I would have gone with coast fab or something similar but I need adjustability. Our pad has neighbours that complain to the city about noise every once in a while and I need the ability to go from fully open at other pads to 3-4 plates at our own pad and on the street… most people don't bother here and keep the OEM exhaust.